Hitherto, water-absorbent resins have been large in absorption rate, absorption amount, and retainability for aqueous liquids and therefore, for uses of the sanitary materials such as diapers, utilized as components of absorbent structures of the sanitary materials by, if necessary, being mixed with fibrous materials.
In recent years, the ratios of the water-absorbent resins in the absorbent structures tend to increase with the increasing needs of the thinning of the sanitary materials such as diapers (e.g. refer to patent document 1 below).
[Patent Document 1] pamphlet of WO 95/26209
As the ratios of the water-absorbent resins in the absorbent structures increase, it has become increasingly necessary to develop, as a future water-absorbent resin, an aqueous-liquid-absorbing agent which combines performances of conventional water-absorbent resins and performances provided by the fibrous materials in conventional absorbent structures.
Examples of the performances demanded to such an aqueous-liquid-absorbing agent include: a performance of rapidly absorbing an aqueous liquid to which the performances of the fibrous materials greatly contribute; a performance of diffusing the aqueous liquid after having absorbed it; and a performance of being capable of retaining the aqueous liquid after having absorbed it; to say nothing of performances of absorbing and retaining the aqueous liquid without load and under load.